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That doesn't work... The turbo is what would be pumping air into the room. It's the variable. The room is the engine, it's the constant.

I specifically said the concept is similar, it helps you get an idea. But you still have volume and PSI in both scenarios. The nubers are different not the theory. Besides the WG keeps airflow of the turbo constant. Why is it so hard to understand this?

Theres a certain amount of volume within a restriction.This volume within the restriction has a mass. The numeric values of volume and mass are dependent not only in PSI, but turbo size as well. If a t25 flows 200 CFM at 18psi and a T88 flow 500 CFM at 18 PSI. Which is producing more airflow with more mass, making higher cylidender pressures thus making more power?

Its simple physics, more specifically thermodynamics.

05-24-2012 07:23 PM

amoosenamedhank

Quote:

Originally Posted by EnJoIthaReX

X2..Well stated my friend

What? Your intake tract might not be a variable but whats inside of it is. Do you understand how PSI, CFM, and VFR are all related? Changing the turbo will change this, or what would be the point in a turbo upgrade?

Thats why when you read compressor maps your either plotting of CFM or MFR (lb/min) on the X axis. Psi is figured in the Pressure ratio along the Y axis.

OP you have alot of reading to do. Even going off the garret site alone isnt enough. They too, over simplify things.
Heres little preview
Psi=Restriction.
CFM (cubic feet per min)=How fast the air is flowing
CFM is a measurement of VFR (volumetric Flow rate)

If turbos are too difficult to understand. Think of 2 rooms. 1 room is 10 X 10 and the other is 20 x 20. If you fill both rooms to 100psi and theyre both the same temp, and you hold the pressure. Which has more air? The larger. Sure if you decrease the temp in the smaller room you can get more air. But the same could be said for the larger. Or more psi would mean more air in both rooms. Get it?....This is similar to how turbos work. But this concept is stationary in y example.

That doesn't work... The turbo is what would be pumping air into the room. It's the variable. The room is the engine, it's the constant.

05-24-2012 06:34 PM

EnJoIthaReX

Quote:

Originally Posted by sporadic

This is not accurately stated. The CFM most certainly is dictated by the turbo, by both the turbine side and the compressor side.
A small turbine housing will restrict flow, and a small compressor will restrict flow.
There is too much over-simplification in your explanation and the original poster needs to do far more reading on their own rather than expect to get all the answers here by non-professionals, including myself.
Go to the Garrett website and read everything before accepting anything you read here as fact.

EDIT: I'll add that I recommend not buying a single piece of your turbo kit until you can read, understand, and plot points on a compressor map relative to your power goals.
If you don't want to do any of this, then just buy a pre-made kit from a company that has done all the research already.

X2..Well stated my friend

Quote:

Originally Posted by amoosenamedhank

Regardless of what you have for a turbo, your intake track and combustion chamber are not variables. Changing your turbo sizing will not change this. A larger turbo will reduce back pressure, this will result in better evacuation of the combustion chamber...therefor improving the VE of the engine.

What? Your intake tract might not be a variable but whats inside of it is. Do you understand how PSI, CFM, and VFR are all related? Changing the turbo will change this, or what would be the point in a turbo upgrade?

Thats why when you read compressor maps your either plotting of CFM or MFR (lb/min) on the X axis. Psi is figured in the Pressure ratio along the Y axis.

OP you have alot of reading to do. Even going off the garret site alone isnt enough. They too, over simplify things.
Heres little preview
Psi=Restriction.
CFM (cubic feet per min)=How fast the air is flowing
CFM is a measurement of VFR (volumetric Flow rate)

If turbos are too difficult to understand. Think of 2 rooms. 1 room is 10 X 10 and the other is 20 x 20. If you fill both rooms to 100psi and theyre both the same temp, and you hold the pressure. Which has more air? The larger. Sure if you decrease the temp in the smaller room you can get more air. But the same could be said for the larger. Or more psi would mean more air in both rooms. Get it?....This is similar to how turbos work. But this concept is stationary in y example.

05-24-2012 01:27 PM

amoosenamedhank

Quote:

Originally Posted by sporadic

This is not accurately stated. The CFM most certainly is dictated by the turbo, by both the turbine side and the compressor side.
A small turbine housing will restrict flow, and a small compressor will restrict flow.
There is too much over-simplification in your explanation and the original poster needs to do far more reading on their own rather than expect to get all the answers here by non-professionals, including myself.
Go to the Garrett website and read everything before accepting anything you read here as fact.

EDIT: I'll add that I recommend not buying a single piece of your turbo kit until you can read, understand, and plot points on a compressor map relative to your power goals.
If you don't want to do any of this, then just buy a pre-made kit from a company that has done all the research already.

Regardless of what you have for a turbo, your intake track and combustion chamber are not variables. Changing your turbo sizing will not change this. A larger turbo will reduce back pressure, this will result in better evacuation of the combustion chamber...therefor improving the VE of the engine.

05-24-2012 12:23 PM

sutyak

Quote:

Originally Posted by amoosenamedhank

The CFM rating is not dictated by the turbo, but instead by the displacement of the engine and the rpms you're at. That is a constant unless you change something in the system.

This is not accurately stated. The CFM most certainly is dictated by the turbo, by both the turbine side and the compressor side.
A small turbine housing will restrict flow, and a small compressor will restrict flow.
There is too much over-simplification in your explanation and the original poster needs to do far more reading on their own rather than expect to get all the answers here by non-professionals, including myself.
Go to the Garrett website and read everything before accepting anything you read here as fact.

EDIT: I'll add that I recommend not buying a single piece of your turbo kit until you can read, understand, and plot points on a compressor map relative to your power goals.
If you don't want to do any of this, then just buy a pre-made kit from a company that has done all the research already.

05-24-2012 11:16 AM

amoosenamedhank

Quote:

Originally Posted by zetecfocus

But doesn't the turbine push a certain psi based on wastegate springs? In return only pushes a certain CFM correct?

The term "PSI" is a measurement of restriction. One turbo may have to spin much faster than another to obtain a the same psi. If you're running a certain turbo passed it's efficiency range, you're only heating up the exhaust gasses/intake charge and losing hp. This is why you compare compressor maps to see what is the best size turbo for you.

Remember 10psi is 10psi. The increase in power is achieved by a cooler/denser intake charge. More air molecules can occupy the same space with a lower temp. Not only this but a larger turbo will help to reduce back pressure which will increase your overall VE of the engine.

The CFM rating is not dictated by the turbo, but instead by the displacement of the engine and the rpms you're at. That is a constant unless you change something in the system.

05-24-2012 08:29 AM

zetecfocus

Yea that's a possibility

05-24-2012 08:03 AM

o_so_slo

Or get a cheap stock one from a junk har or I'm sure someone on here would give one away to you very easy to come by. I actually just threw one out last month lol

05-24-2012 07:39 AM

zetecfocus

Quote:

Originally Posted by zetecfocus

Well my only dilemma is, I have a long tube header now. So with FSWerks I would have to purchase a turbo manifold.

Therefore, the top speed is becoming more appealing.

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